Naphtha soluble soap



Patented June 22, 1937 UNITED STATES I 2,084,483 NAPHTHA sonunm soar-Theodore a. Domain,

Irvingto to Standard Oil Development Company, a

poration of Delaware n, N. J., assignor cor- No Drawing. ApplicationOctober 29, 1932, Serial 6 Claims.

This invention relates to improvements in the art of soap compositionsand more particularly to improved soap compositions which are readilysoluble in hydrocarbon solvents and which are particularly adaptable foruse as a dry cleaners soap in the cleaning of textile fabrics, clothing,and the like.

It has been found that an improved soap composition may be prepared bymixing oil-soluble ,0 sulfonates with fatty acid soaps in suitableproportions. The sulfonates may be derived from petroleum oils bytreating the same with strong or fuming sulfuric acid, separating theresulting so-called oilsoluble sulfonic acids from the ,5 treated oiland converting the sulfonic acids into the corresponding ammonium oralkali metal salts. Especially suitable sulfonates are the socalledemulsifiable sulfonates, which form solutions in hydrocarbon oils thatemulsify readily when added to water. Such sulfonates are characterizedby substantial freedom from inorganic salts. They may be prepared fromacid treated petroleum oil, in which fuming acid treated oil, afterseparation of sludge, is neutralized with an alkali such as caustic sodaor sodium carbonate and then washed with aqueous alcohol. The aqueousalcohol extracts sulfonate soaps and inorganic salts from the oil. Thisaqueous alcohol solution may be evaporated to dryness and an improvedsulfonate obtained by extraction from the residue with strong alcohol.The aqueous alcohol solution may also be treated with a dehydratingagent, such as anhydrous sodium carbonate or sodium carbonatemonohydrate, in suflicient quantity to substantially dehydrate thealcohol. The alcohol is then settled, filtered if necessary, andevaporated to dryness, leaving as a residue the purified emulsiflableoil soluble sulfonates.

The fatty acid soaps suitable for use with these sulfonates include thesoaps derived from the saturated and unsaturated fatty acids ofpreferably about 12 to 20 carbon atoms and the acids of correspondingmolecular weight obtained by limited oxidation of paraflin wax. It hasbeen found that the presence of a certain amount of water aids the easeofpreparation of the soap composition and also the ease of its solutionin dry cleaners naphtha or other hydrocarbon and similar solvents.

It has also been found desirable to add a heavy oil, such as a viscouslubricating oil, to the soap composition. This 011 aids in the solutionof the soap in the lighter hydrocarbons customarily used and also is ofadvantage in maintaining the "life of clothing and other fabrics whichare cleaned with a naphtha solution of this soap compositio It is wellknown that in ordinary dry cleaning, fabrics become harsh to the touchand lose many desirable characteristics after being dry cleaned three orfour times. The use of aviscous hydrocarbon oil fraction in the soapcomposition serves to prevent this degradation of the goods-cleaned.This oil is preferably a highly refined petroleum white oil, that is, aviscous fraction of a petroleum oil which has been treated with anexcess of strong or fuming sulfuric acid to remove all asphaltic,resinous and unstable constituents. The following example illustrates apreferred method for preparing my improved soap composition but it isunderstood that my invention is not to be limited tothe particularprocess described, nor'to the particular composition stated: Ten poundsof an oil-solublesodium sulfonate derived from a fuming sulfuric acidtreated lubricating fraction of a petroleum oil are mixed with fiftypounds of a viscous petroleum white oil until complete solution occurs.Sufiicient commercial oleic acid, bleached elain oil or red oil is thenadded with stirring to be the equivalent of twenty pounds of potassiumoleate in the finished composition. Twenty pounds of water, containingin solution the equivalent amount of potassium hydroxide necessary forneutralization of the oleic acid, are then added slowly to the oil withvigorous stirring or crutching. This operation may be conductedsatisfactorily at roomtemperature, although a slight rise in temperaturedue to the heat of neutralization of the oleic acid is notobjectionable. The mixture is crutched until there is secured as theproduct a stiff transparent I clear jell or paste which is the improvednaphthasoluble soap. This soap works into dry cleaners naphtha. orVarsol easily and forms clear and stable solutions therein. It improvesthe ease and effectiveness of the cleaning operation when used in suchvolatile solvents for dry cleaning clothing and the like. Varsol is avolatile petroleum distillate having a gravity of at least A. P. I.,Saybolt color of 22, low sulfur of about .05%, non-corrosive, andshowing no color reaction of contacting with sodium plumbite and sulfur.This distillate, on redistilling, should be at. least volatile at 350 F.andvolatile at 392 F. with a final end point of not over 410 F.

While the soap may be used in any desired proportion in dry cleaningcompositions, a very small amount will usually be found satisfactory;for example, about 1 to 5 or 10 pounds of the improved naphtha-solublesoap per 100 gallons of VarsoP' or other suitable solvent.

My improved naphtha-solublev soap may be prepared by various othermethods than that described above. For example, the sulfonic acids andfattyacids may be neutralized together; a part or all of the sulfonicacids may be used as fat splitting agents for obtaining fatty acids andthe mixture may be neutralized directly, or after solution in a heavyhydrocarbon oil, with a suitable alkali.

While the relative proportions of the constituents used in my improvednaphtha-soluble soap may vary widely, it has been found that anespecially desirable composition is obtained if the.

concentrations of the'constituents are held within certain approximatelimits. If the soap composition is prepared with less than about 7% ofsulfonates, it is obtained as a resilient composition of the type knownas a singing jell. This composition disolves in volatile hydrocarbonsolvents such as Varsol with somewhat more difficulty than do thepreferred compositions containing about 10% to 25% or more oi.-sulfcnates.

The amount of fatty acid soap will be about 10 to 30% by weight ofthetotal composition. The

amount of water is preferably about equal to that of the fatty acidsoap. If too little water-is used a hard and tough composition resultswhich is very difficult to work while if too much water is used thestability of the finished composition is impaired. In general the amountof water in the preferred composition will be about 10 to 30% and willalso be within about 5% 'of the amount of fatty acid soap used. Theheavy hydrocarbon oil may be used. in substantially any proportion,althoughfrom about 30 to 70% I is considered the preferred range for itsconcentration.

This invention is not to be limited to any speciflc examples which arepresented herein solely for illustration, nor to any theories regardingthe composition of my products, but only by the following claimsin whichI- wish to claim all novelty insofar as the prior art permits.

I claim:

1. Improved naphtha soluble soap composi tion comprising about 20% byweight of potassium oleate, 20% of water, 10% of oil-soluble in thefinished composition, and then adding slowly with stirring 20 parts ofwater containing the equivalent amount of potassium hydroxide necessaryfor neutralization of the oleic acid.

3. Improved dry-cleaning composition comprising a dry-cleaner's petroeum naphtha con-,- taining in solution a soap compositioncontainingabout 10 to 30% of potassiumoleate, a substantiallyequalamount of water and any oil soluble alkali metal sulfonate derivedfrom a fuming sulfuric acid treated lubricating fraction v of apetroleum oil in an amount not less than 7%, and a major proportion of aheavy hydrocarbon oil.

grslmproved naphtha-soluble dry-cleaning soap composition comprisingabout 10 to 30% of potassium oleate, a substantially equal amount ofwater, and an oil soluble alkali metal sulfonate obtained from petroleumoils in an. amount not less than 7%, and-a major proportion of a heavyhydrocarbon ofl.

5. Improved naphtha-soluble dry-cleaning soap composition comprisingabout 10 to 30% of an alkali metal soap of a fatty acid of about 12 to20 7% and a major proportion of a heavy hydro- THEODORE R. Dom-AN. 54

carbonoil.

